Example: Convert an ESRI Personal Geodatabase into a .map Project

This topic shows how to convert data in ESRI's legacy personal
geodatabase format into a Manifold .map
project in a single step.

ESRI's personal geodatabase
format is the original ArcGIS "geodatabase" format. Data
in a personal geodatabase is stored and managed in Microsoft Access .mdb files, and thus subject to
all the limitations and inconveniences of .mdb
format in a 64-bit world. Personal geodatabases are limited to 2
GB, with performance typically degrading between 250 MB and 500
MB.

ESRI users seem to agree that personal geodatabases as a format are
on their way out, being replaced by file
geodatabases. Manifold users will want to convert their personal
geodatabases into either Manifold .map
projects for immediate, high-speed use or into ultra-compact Manifold
.mxb archive files for archival
storage and exchange.

Lucky for us, Manifold's Export capability
can convert an entire ESRI personal geodatabase into a .map or
.mxb project in a single step.

We will illustrate export of a personal geodatabase containing information
on New York city in the United States published by Baruch College. Non-profit
organizations using the free Manifold Viewer for analytics can more easily
access this data in .map or .mxb form, which the license for
the data allows.

The "geodatabase" consists of a Microsoft Access .mdb
file called nyc_gdb_july2017.mdb.

Launch Manifold in 32-bit Mode

If we are running a 64-bit Windows operating system we must launch Manifold
in 32-bit mode so we can link
the .mdb Access database into
Manifold without having to worry if our particular Windows installation
has been retrofitted to talk to Microsoft .mdb.

Link the Personal Geodatabase as a Data Source

We launch Manifold in 32-bit
mode and choose File - Link.

We navigate into the folder that holds the nyc_gdb_july2017.mdb
file. We click on the nyc_gdb_july2017.mdb
file and choose Open.

There is no need to specify the file type since the Manifold dataport
for .mdb automatically swings
into action.

A new data source called nyc_gdb_july2017
appears in the project.

Export the Data Source

We click on the + box by the
name of the data source to expand the data source, to see the many drawings
and tables that are stored in the geodatabase. Next,
we Right-click onto the nyc_gdb_july2017 data source.

From the context menu that appears we choose Export.

In the Export dialog, if we
want to export to a .map file
we choose MAP Files as the type.
We provide a name for the new .map
file and we press Save. Done!

In the Export dialog, if we
want to export to an .mxb file
we choose MXB Files as the type.
We provide a name for the new .mxb
file and we press Save. Done!

We can see a new .map project
has been created by opening the newly-created .map
file.

In a new, blank Manifold session, which could be 64-bit Manifold running
in 64-bit Windows, we choose File
- Open.

We navigate to where we saved our .map
and, if we also exported it, our .mxb
files. We click on the .map
and choose Open.

The .map project opens instantly,
and we see that the export process did, indeed, convert all of the nyc_gdb_july2017.mdb personal geodatabase
content into a single, high-performance .map
project.

If we had opened the Manifold .mxb archive,
we would have reconstituted the above project as well. The
only difference would be that the .mxb
would not open instantaneously as does Manifold's everyday working format,
.map.

Operational File Sizes Compared

We can compare file sizes when storing the same spatial data in ESRI
form or Manifold form.

The personal geodatabase in native ESRI personal geodatabase format,
ready for use within ArcGIS, occupies about 67
MB and requires one file.
It also requires use of 32-bit software or use of Microsoft's special
retrofitting of 64-bit Windows using software that clashes with Microsoft
Office. Microsoft MDB format
is also famously fragile.

Converted to a .map the spatial
data occupies about 110 MB, roughly
40% larger than the original ESRI file geodatabase, but ready for use
in 32-bit or 64-bit software. The .map
file, of course, is also fully parallel Radian technology delivering speed
many times faster than possible with Microsoft .mdb
format, while being famously bulletproof.

Archival File Sizes Compared

Manifold's MXB archive and exchange
format has been designed to compress Manifold projects as good as or better
than zip technology. When converting a personal
geodatabase into a Manifold project the resulting .mxb
archive file will usually be significantly smaller than a zip file containing
the personal geodatabase in Microsoft Access .mdb
format. With file geodatabases a zipped geodatabase will often
be about the same size as an equivalent .mxb
archive file or even slightly smaller.

In the case of the nyc_gdb_july2017.mdb
personal geodatabase, when the .mdb is
zipped the zip file requires 29
MB. The equivalent Manifold .mxb file is about 27
MB, slightly smaller, a typical result.

Notes

Personal geodatabases
- The original ArcGIS geodatabase format. Data stored and managed
in Microsoft Access .mdb files,
and thus subject to all the limitations and inconveniences of .mdb format in a 64-bit world. Limited
to 2 GB with performance typically degrading between 250 MB and 500
MB. ESRI users seem to agree that personal geodatabases as a
format are on their way out, being replaced by file geodatabases.

File geodatabases -
A new "geodatabase" format introduced by ESRI in ArcGIS
9.2. Stores data within a folder in the Windows file system
in the form of very many files, all of which must travel together
in an ensemble to avoid damage. The tiny NapervilleGas
example published by ESRI and used in this documentation requires
857 separate files.

Manifold can link into a project as a data source all of the above three
ESRI geodatabase formats.

Viewer is Free - Manifold Viewer
provides a free viewer to explore and to analyze sophisticated databases.
Although Viewer is perfectly capable of connecting to the
above three different forms of ESRI geodatabases, it makes way more sense
to publish such data in the form of .mxb files
for people who are using Viewer.